Fastening device



FIG. 1 is a top, back, left side perspective view of a fastening device;

FIG. 2 is bottom, front, right side perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a back view thereof;

FIG. 5 is top view thereof;

FIG. 6 is a bottom view thereof; and,

FIG. 7 is a right side view thereof, the left side being a mirror image of. 

CLAIM The ornamental design for a fastening device, as shown and described. 